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avoid_non_null_assertion

Rule which warns about usages of bang operator ("!") as it may result in unexpected runtime exceptions.

Types with index operator (like [Map], IMap, BuiltMap) can be ignored using ignored_types config parameter.

Example config:​

solid_lints:
  diagnostics:
    avoid_non_null_assertion:
      ignored_types:
        - Map
        - IMap
        - BuiltMap

Example​

BAD:​

Object? object;
int? number;
final map = {'key': 'value'};

final int computed = 1 + number!; // LINT
object!.method(); // LINT
map['key']!; // LINT (unless Map is in ignored_types)

GOOD:​

Object? object;
int? number;

if (number != null) {
  final int computed = 1 + number;
}
object?.method();

// Allowed if Map is in ignored_types
final map = {'key': 'value'};
map['key']!;

Parameters​

ignored_types (String | List<String> | Map<String, Object?>)​

Types that would be ignored by avoid-non-null-assertion rule

Example:

solid_lints:
  diagnostics:
    avoid_non_null_assertion:
      ignored_types:
        - Map
        - IMap
Map<String, String> map;
map['key']!; // OK